Please protest public health by continuing to restrict use of back-up generators to unplanned outages. These generators are highly polluting and should be used only in emergencies. In particular, if non-emergency use is allowed at all, it must be prohibited near “sensitive receptors” such as schools, hospitals and residential areas), and the public should be given notice about where and when these generators will be running and for how long. Daily monitoring should also be required. But, again, the best approach is not to allow non-emergency use at all.